This invention relates to new and useful antibacterial agents. More specifically, it is concerned with a novel class of cephalosporin derivatives which possess broad-spectrum antibacterial activity, especially against the Gram-negative microorganisms. In particular, the compounds of the invention constitute a series of 7-(.alpha.-aminoarylacetamido)-.DELTA..sup.3 -cephem derivatives with a novel type of acyl moiety attached to the .alpha.-amino group.
In the past, various attempts have been made by numerous investigators in the field of chemotherapy to obtain new and better antibacterial agents. For the most part, these efforts have involved the synthesis and testing of various new and heretofore unavailable organic compounds, particular in the area of semi-synthetic antibiotics like the cephalosporin derivatives. For instance, D. A. Cox et al. in Belgian Pat. No. 819,798 disclose various 7-(D-.alpha.-acylaminoarylacetamido)cephalosporanic acid derivatives useful for these purposes. However, in the search for still new and more improved antibacterial agents, little is known about the effect of an epoxy linkage on compounds of this type and particularly, an epoxy group directly attached to the carbonyl carbon atom of the aforesaid acylamino moiety of which it forms a part.